2469-45-6Relevant academic research and scientific papers
B(C 6 F 5) 3 -Catalyzed Reduction of Sulfoxides and Sulfones to Sulfides with Hydrosilanes
Porwal, Digvijay,Oestreich, Martin
, p. 4698 - 4702 (2017/10/05)
B(C 6 F 5) 3 is shown to catalyze the deoxygenation of sulfoxides and sulfones to the corresponding sulfides with Et 3 SiH as the stoichiometric hydride source. While the method is limited in terms of functional group tolerance, it is applicable to the reduction of alkyl/aryl-, aryl/aryl-, and alkyl/alkyl-substituted sulfoxides, including the benzyl/benzyl-substituted derivative. The same protocol converts alkyl/aryl- but not aryl/aryl-substituted sulfones into sulfides.
Hydrodeoxygenation of sulfoxides to sulfides by a Pt and MoOx co-loaded TiO2 catalyst
Touchy, Abeda Sultana,Hakim Siddiki,Onodera, Wataru,Kon, Kenichi,Shimizu, Ken-Ichi
, p. 2554 - 2560 (2016/05/19)
Supported metal nanoparticle catalysts were studied for the hydrodeoxygenation of sulfoxides to sulfides under solvent-free and mild conditions (50-155 °C, 1 or 7 atm H2). The catalytic activity for the model reaction of diphenyl sulfoxide depended on the type of metals, support materials and co-loaded oxides of transition metals (V, Nb, Mo, W, Re). Pt and MoOx co-loaded TiO2 (Pt-MoOx/TiO2) showed the highest activity. Pt-MoOx/TiO2 was reusable after the reaction and was effective for the reduction of various sulfoxides and showed a higher turnover number (TON) than previously reported catalysts. Using Pt-MoOx/TiO2, benzylphenylsulfone was reduced by H2 to give phenylbenzyl sulfide via benzylphenyl sulfoxides, which represented the first example of catalytic conversion of a sulfone to a sulfide by H2. Characterization studies of Pt-MoOx/TiO2 show that the surface of TiO2 is covered by small (or thin layer) Mo oxide species with exposed Mo cations as Lewis acid sites, and 4-5 nm sized Pt metal nanoparticles are supported on the Mo oxide-covered TiO2.
Cu-Fe-S Nanocrystals Exhibiting Tunable Localized Surface Plasmon Resonance in the Visible to NIR Spectral Ranges
Gabka, Grzegorz,Bujak, Piotr,Ostrowski, Andrzej,Tomaszewski, Waldemar,Lisowski, Wojciech,Sobczak, Janusz W.,Pron, Adam
supporting information, p. 6660 - 6669 (2016/07/19)
Cu-Fe-S nanocrystals exhibiting a strong localized surface plasmon resonance (LSPR) effect were synthesized for the first time. The elaborated reproducible preparation procedure involved copper(II) oleate, iron(III) stearate, and sulfur powder dissolved in oleylamine (OLA) as precursors. The wavelength of the plasmonic resonance maximum could be tuned by changing the Cu/Fe ratio in the resulting nanocrystals, being the most energetic for the 1:1 ratio (486 nm) and undergoing a bathochromic shift to ca. 1200 nm with an increase to 6:1. LSPR could also be observed in nanocrystals prepared from the same metal precursors and sulfur powder dissolved in 1-octadecene (ODE), provided that the sulfur precursor was taken in excess. Detailed analysis of the reaction mixture by chromatographic techniques, supplemented by mass spectrometry and 1H NMR spectroscopy enabled the identification of the true chemical nature of the sulfur precursor in S/OLA, namely, (C18H35NH3+)(C18H35NH-S8-), a reactive product of the reduction of elemental sulfur by the amine groups of OLA. In the case of the S/ODE precursor, the true precursors are much less reactive primary or secondary thioethers and dialkyl polysulfides.
Reductive coupling of disulfides and diselenides with alkyl halides catalysed by a silica-supported phosphine rhodium complex using hydrogen as a reducing agent
Zhang, Hean,Hu, Mangen,Cai, Mingzhong
, p. 645 - 647 (2013/11/06)
The reductive coupling of disulfides and diselenides with alkyl halides was achieved in THF at 65 °C in the presence of 3 mol% of a silica-supported phosphine rhodium complex and triethylamine using hydrogen as a reducing agent, affording a variety of unsymmetrical sulfides and selenides in high yields. The heterogeneous rhodium catalyst can be recovered by a simple filtration and reused several times without significant loss of activity. Reaction with an acyl halide was also observed.
Lewis acid-promoted electron transfer deoxygenation of epoxides, sulfoxides, and amine N-oxides: the role of low-valent niobium complexes from NbCl5 and Zn
Oh, Kyungsoo,Knabe, William Eric
experimental part, p. 2966 - 2974 (2009/05/30)
A mild and operationally simple deoxygenation of epoxides, sulfoxides, and amine N-oxides is described using a sub-stoichiometric amount of low-valent niobium complexes generated in situ from commercially available NbCl5 and zinc dust. The deoxygenation proceeds by a reductive cleavage of polarized O-C/O-N/O-S bonds through a single electron transfer from zinc metal to the niobium-substrate complex due to the high oxophilic nature of the niobium species. The presence of adjacent radical-stabilizing groups is beneficial to epoxide substrates; however the similar prerequisite does not apply to sulfoxides and amine N-oxides, where a broad range of substrates are efficiently deoxygenated in excellent yields.
Rhodium-catalyzed reductive coupling of disulfides and diselenides with alkyl halides, using hydrogen as a reducing agent
Ajiki, Kaori,Hirano, Masao,Tanaka, Ken
, p. 4193 - 4195 (2007/10/03)
(Chemical Equation Presented) We have established that RhCl(PPh 3)3 catalyzes a reductive coupling of disulfides and diselenides with alkyl halides in the presence of triethylamine using hydrogen as a reducing agent. This reaction serves as a convenient new method to produce unsymmetrical sulfides and selenides from disulfides and diselenides instead of unstable and odoriferous thiols and selenols.
Hydrophobic polymer-supported catalyst for organic reactions in water: Acid-catalyzed hydrolysis of thioesters and transprotection of thiols
Iimura, Shinya,Manabe, Kei,Kobayashi, Shu
, p. 101 - 103 (2007/10/03)
(Matrix presented) A hydrophobic polystyrene-supported sulfonic acid was found to be effective for hydrolysis of thioesters in pure water. It was revealed that the catalyst was much superior to other Bronsted acid catalysts. Transprotection of thiols from thioesters to thioethers has been successfully performed in water using this catalytic system.
Deoxygenation of sulfoxides and selenoxides with nickel boride
Khurana, Jitender M.,Ray, Abhijit,Singh, Sarika
, p. 3829 - 3832 (2007/10/03)
The deoxygenations of a variety of acyclic sulfoxides and selenoxides have been reported with nickel boride in THF at 0-5°C in nearly quantitative yields. The deoxygenations are proposed to proceed by an oxidative-addition and reductive-elimination mechanism.
Desulfurization with Nickel and Cobalt Boride: Scope, Selectivity, Stereochemistry, and Deuterium-Labeling Studies
Back, Thomas G.,Baron, Denise L.,Yang, Kexin
, p. 2407 - 2413 (2007/10/02)
A variety of organosulfur compounds containing alkylthio and arylthio groups underwent reductive desulfurization under notably mild conditions when treated with nickel boride, generated in situ from nickel chloride hexahydrate and sodium borohydride in methanol-THF (3:1).Phenyl, chloro, and ester groups are not reduced under these conditions, while iodo, bromo, nitrile, aldehyde, ketone, cyclopropane, and olefinic functions are reduced either completely or partially.Deuterium-labeling studies indicate that the hydrogen that is incorporated into the product originates from both the sodium borohydride and the protic solvent, suggesting the intermediacy of dihydrogen.The epimers 3α- and 3β-(phenylthio)cholestane afforded 3α- and 3β-deuteriocholestane, respectively, demonstrating that the reaction proceeds with retention of configuration.The method may thus be employed for the stereospecific preparation of deuterated products from organosulfur compounds.Arguments are presented in support of a tentative mechanism involving an oxidative addition-reductive elimination sequence via a nickel hydride intermediate.
UNE METHODE SIMPLE DE SYNTHESE DES PHOSPHATES TERPENIQUES ALLYLIQUES PRIMAIRES ET TERTIAIRES.
Julia, M,Mestdagh, H.,Rolando, C.
, p. 3841 - 3850 (2007/10/02)
Alkylation of tetrabutylammonium dihydrogenophosphate by terpenic allylic sulphonium salts give the corresponding primary terpenic allylic phosphates in fair to moderate yields, without complex procedures of purification.The catalysis of the reaction by cuprous ion leads to the isolation of tertiary allylic phosphates.
